One of the more important activities for medical safety is the disposal of used medical instruments, and particularly disposable, metallic, hypodermic needles. Disposable hypodermic needles are widely used in hospitals and other medical facilities to draw body fluids from, and to inject medications into, patients. These needles are made disposable because of the difficulties, and inefficiencies, involved in sterilizing and sharpening hypodermic needles for reuse. Inasmuch as the needles are intended to be discarded after use, a problem arises as to their safe post-use storage and disposal.
In virtually every state it is illegal to discard used hypodermic needles as ordinary waste inasmuch as their sharp points, as well as the disease organisms carried on such needles, may injure hospital and/or waste disposal personnel. Moreover, there is also the very important need to prevent the disposed needles from being used by others, either recklessly or for illegal purposes. Because the current state of the art relating to the destruction of hypodermic needles is so unsatisfactory, untold quantities of such medical instruments are not being destroyed after use but are being illegally foisted on the enviromnent, with disastrous results.
Many systems and apparatus, both mechanical and electrical, have been proposed over the years, but the prior proposals have each been deemed to be unsatisfactory.
For example, the prior known mechanical systems for hypodermic needle destruction have simply either crushed or broken the needles. Although these devices do prevent the reuse of the needles, such devices often serve to multiply the number of sharp points available inadvertently to pierce unwary humans. In addition, such disposal does not, in any way, neutralize any body fluids inadvertently retained on, or in, the needles. One example of such an arrangement is disclosed in U.S. Pat. No. 4,531,437 issued on Jul. 30, 1985.
In order to attempt to neutralize the body fluids retained in, or on, the needles, as well as any disease organisms present in those fluids, incineration of the disposable needles has also been utilized. Bulk incineration of accumulated needles, however, poses the continued threat of injury during that period of time beginning immediately following their usage and extending until the needles are actually received in the incinerator. Moreover, if the incinerating temperature is not sufficient to destroy the needle it continues to be a hazard, an unfortunate situation that has occurred in the past.
The period of potential exposure to needles that are contaminated has been reduced by supplying portable devices that are available to incinerate the needles electrically immediately after they have been used. The prior known electrical systems generally use electrical resistance heating to incinerate the needle. These systems have used both stationary electrodes, or relatively movable electrodes. One form of the movable electrode systems encompass arrangements wherein the needle is moved relative to the electrode, such as disclosed in U.S. Pat. No. 4,877,934, issued Oct. 31, 1989. In other forms of the movable electrode systems one of the electrodes is rotated relative to the needle, such as disclosed in U.S. Pat. No. 5,138,124, issued on Aug. 11, 1992. Heretofore, movable electrode systems, without further processing of the needle, leave at least one portion of the needle with a sharp end, even after the needle has been significantly destroyed.
The stationary electrode systems, such as that shown in U.S. Pat. No. 4,965,426 issued Oct. 23, 1990, are similar to the movable electrode systems currently in use. However, these systems generally do not destroy as much of the overall length of the needle as the movable systems do. These systems rely on the melting process to leave a rounded end, and thus do not assure the operator that the end is indeed blunt.
Even in the most advanced of the prior known systems the swarf must eventually be emptied, and most workers are fearful of having to open the apparatus to empty the residue. Even though they know that the swarf does not contain sharp points, they are fearful of inhaling any dust that might become airborne during the emptying process.
Careful attention has also disclosed that users of the electrical disposal devices are fearful of any gaseous vapor, or electrical sparks, escaping back into the atmosphere during operation of such devices.
It is thus apparent that a need remains for an improved method and apparatus for destroying metallic, medical instruments, and particularly hypodermic needles, in a more effective and efficient manner. The present invention is directed to that objective.